Bascule bridge



A. 'O. CUNNINGHAM Sept; I924.

BASGULE BRIDGE Filed any 5 1920 5 Sheets-Sheet l stp A. 'O. CUNNINGHAM BA 5 CULE BRIDGE Fil y 5 1920 3 Sheets-Sheet 3 Sept. 3fl,'1924. 1,510,043

' 4 A. 0. CUNNINGHAM BASICULE BRIDGE Filed May 5, 1920 :5 sheets-sheet 5 .272 veni'or: uitar-O, Wa m,

41,215 fiiiy.

Patented Sept. 30, 1924.

UNITED STATES ANDREW O. CUNNINGHAM, OF ST. LOUIS, MISSOURI.

BASCULE BRIDGE.

Application filed May 5,

To all whom it may concern:

Be it ,known that I, ANDREW O. CUNNING- HAM, a citizen of the United States, and a resident of St. Louis, Missouri, have in vented a new and useful Improvement in Bascule Bridges, of which the following is a specification.

My invention relates to bascule bridges and .has for its principal objects to facilitate the operation of such bridges, to obviate the necessity for a pit to accommodate the counterweight when the bridge is opened and to simplify the construction of such bridges. Heretofore, it has been common practice to support the trunnions of such bridges on beams. This construction has the disadvantage that the beam is liable to deflect and thus make the operation of the bridge more difiicult. While this disadvantage has been recognized, it has not been considered feasible to support the trunnions on columns, because in ordinary constructions the columns are in the line of movement of the counterweights and limit the upward swing of the movable leaf. My invention avoids these disadvantages and makes it possible to sup port the trunnions on columns and dispose the counterweights so that they will clear the columns. The invention consists principally in offsetting the counterweights and in supporting the trunnions of the movable leaf of the bridge directly upon columns. The invention further consists in the parts and combinations of parts hereinafter described and shown.

Fig. 1 is a side elevation of a bascule bridge embodying my invention;-

Fig. 2 is a top plan View thereof;

Fig. 3 is a horizontal sectional view on the line 33 of Fig. 1;

Fig. 4 is an end elevation of said bridge;

Fig. 5 is a vertical sectional view on the line 55 of Fig. 1;

Fig. 6 is a plan view of a modified form of the invention; and

Fig. 7 is an end view of the bridge shown in Fig. 6.

The movable leaf 1 of a bascule bridge is pivotally mounted, as by trunnions 2, on columns 3. Said columns 3 are supported on the bridge foundations 41 and are provided with braces extending therebetween. The roadway is indicated in dash lines.

The upper truss members 5 at the end of the movable leaf 1 have web plates 6 secured thereto. Transverse girders 7 comprising 1920. Serial No. 378,964.

channel irons or the like are secured to said plates 6. Said girders are secured to counter weights 8 by suitable gusset plates 9. Said girders 7 project at each end beyond the vertical plane passing through the column and the truss members of the bridge so that said counterweights 8 are laterally offset from the columns 3 and will clear the columns when the leaf 1 is operated. The diagonal struts 10 of the end truss are also orovided with similar transverse girders 11 and web plates 12. The lower marginal portions of said counterweights 8 are secured to longitudinal truss members 13 which are racks 16. The bridge is operated by pinions 17 cooperating with said racks, said pinion being rotated by any suitable means.

The structure and location of the counterweights are such that there is no necessity for a pit to accommodate the counterweights when the movable leaf is swung upwardly. The trunnions are held in alinement and the counterweights clear the columns. It is possible to keep the roadway open while building the bridge.

In Figs. 1 to 5 inclusive, the counterweights are shown outside of the column lines, and this is the preferred construction.

In Figs. 6 and 7, is illustrated an alternative construction in which the counterweights 8 are supported inside of the lines of the col umns. In this construction, the counterweights are preferably supported at the ends of the longitudinal truss members 50 of the bridge, said truss members being braced by suitable cross girders 51, as above described. As above described, the weight of the bridge is supported directly on the columns 3.

The counterweights are provided with suitable bracing members 52, extending from one counterweight to the other. In the construction shown in Figs. 1 to 5, the brace members must be omitted from the lower portions of the counterweights, so that there will be nothing to strike against the columns 3.

The trunnions may be supported below the level of the track if desired, and other changes may be made without departing from my invention; and I do not wish to be limited to the precise construction shown.

What I claim is:

1. A bascule bridge comprising a single pair of columns, a leaf pivotally supported on said columns to swing vertically, and counterweights for said leaf, the truss members of the leaf being in line with the respective columns and said counterweights being offset laterally from the body of the leaf far enough to clear the respective columns. v

2. A bascule bridge comprising columns, a leaf pivotally supported directly on said columns to swing vertically, transverse girders secured at the ends of said leaf and counter-weights for said leaf supported by said transverse girders, said countervveights being laterally offset from the body of the leaf far enough to clear the respective colnmns.

A bascule bridge comprising a single pair of columns, a leaf pivotally supported on said column to swing vertically and counterweights for said leaf, the truss members of the leaf being in line with the respective columns and said counterweights being disposed to the side of the columns so as to swing clear thereof.

A bascule bridge comprising a single pair of columns, said columns being provided with braces extending therel'ietwcen, a leaf pivotally supported on said column to swing vertically and counterwcights for said leaf, said counterwcights being disposed to the side of the columns so as to swing clear thereof.

Signed at St. Louis, Missouri, this 30th day of April, 1920.

ANDREW O. CUNNINGT I AM. 

